This largely Ozarkian species was recently collected on sandstone outcrops along roads southwest of Joy in LIVI (JC for KY; M. Homoya for WKY). It has also been reporterd by McFarland (1942) and Grubbs (1989), but the latter was based on a misidentified coll. of caroliniensis from HICK (MUR). Disjunct close relatives of pedunculata to the east of Ky. have been segregated as R. purshiana Fern. and R. pinetorum Fern. (W). R. purshiana occurs close to Ky. in the Ridge-and-Valley of w. Va. and ne. Tenn., but it is unknown within the state. These species differ from the caroliniensis-ciliosa-humilis group as follows (F, W, Y),: flowers borne on peduncles 0.2-7+ cm long (versus sessile or subsessile), from the axils of lower and median nodes, not from the terminal node or terminal cluster (versus lower, median and terminal); capsules puberulent or glabrous (versus glabrous or nearly so); leaves with petioles ca. 3-15 mm (versus 1-10 mm).